Is L-Arginine Good Or Bad For You?

Written by:

Obi Obadike

Obi Obadike

Celebrity Fitness & Nutrition Expert, CFT, SFN, M.S. Founder & CEO – Ethical Inc.
Share on facebook
Share on twitter
Share on linkedin
Share on email

Is L-Arginine good or bad for you? L arginine is safe to take. It is considered an amino acid and it is known to support healthy blood flow, improved athletic performance and recovery during critical illness.

L-Arginine is also known to be research wise for the development of T-cells and it plays a role in immune support response. It acts as a precursor to other amino acids and is vital in heightening the health of your immune system.

Improving Athletic Performance

There was a randomized study that was done on 56 soccer players, and they were given 2 grams of L-arginine daily. And this was for 45 days, and their sports performance significantly increased compared to the placebo group.

Is L-Arginine good or bad for you? Photo credit: iStock-natatravel

Another small study that was done in 9 men who drank a beverage that had 6 grams of L-arginine about 1 hour before an intense exercise. The results showed they were able to exercise longer compared to the placebo group.

There are also mixed studies that showed that L-arginine doesn’t impact exercise performance. So, the studies that are out there favor impacting and not impacting exercise so there are mixed.

Regulating Blood Pressure

Research studies have shown that taking L-arginine supplements can lower your systolic and diastolic blood pressure numbers. In 7 random studies it showed it lowered blood pressure levels with people that had high blood pressure.

Improving Erectile Dysfunction

Some other potential benefits that L-arginine supplements show are helping with erectile dysfunction while improving blood blow. There were 10 research studies in 2009 that showed that daily doses of 1.5 grams of L-arginine improved blood flow in erectile dysfunction compared to a placebo or no treatment.

Research studies also showed that taking L-arginine supplements during pregnancy helped prevent and treat preeclampsia. Preeclampsia is a condition that happens when you have high blood pressure and protein in the urine.

Some of the side effects to L-arginine are if you take large doses which would be 9 grams or more per day. And those side effects are bloating, abdominal pain, nausea, diarrhea, etc.

Some of medicines that L-arginine can interact with safely is:

  • Blood Pressure Lowering medications.
  • Diuretic medications
  • Antidiabetic medications
  • Blood thinning medications
  • Erectile dysfunction medications

If you store it in a cool dry area that will help preserve the quality of the product as opposed to it being exposed to heat or moisture.

The Bottom Line is L-arginine is safe to take and studies have shown that it can help reduce your blood pressure levels. And it can help with improving blood flow and erectile dysfunction.


  1. Rhim HC, Kim MS, Park YJ, Choi WS, Park HK, Kim HG, Kim A, Paick SH. The Potential Role of Arginine Supplements on Erectile Dysfunction: A Systemic Review and Meta-Analysis. J Sex Med. 2019 Feb;16(2):223-234. doi: 10.1016/j.jsxm.2018.12.002. Erratum in: J Sex Med. 2020 Mar;17(3):560. PMID: 30770070.
  2. Facchinetti F, Saade GR, Neri I, Pizzi C, Longo M, Volpe A. L-arginine supplementation in patients with gestational hypertension: a pilot study. Hypertens Pregnancy. 2007;26(1):121-30. doi: 10.1080/10641950601147994. PMID: 17454224.
  3. Camarena Pulido EE, García Benavides L, Panduro Barón JG, Pascoe Gonzalez S, Madrigal Saray AJ, García Padilla FE, Totsuka Sutto SE. Efficacy of L-arginine for preventing preeclampsia in high-risk pregnancies: A double-blind, randomized, clinical trial. Hypertens Pregnancy. 2016 May;35(2):217-25. doi: 10.3109/10641955.2015.1137586. Epub 2016 Mar 22. PMID: 27003763.
  4. Dorniak-Wall T, Grivell RM, Dekker GA, Hague W, Dodd JM. The role of L-arginine in the prevention and treatment of pre-eclampsia: a systematic review of randomised trials. J Hum Hypertens. 2014 Apr;28(4):230-5. doi: 10.1038/jhh.2013.100. Epub 2013 Oct 31. PMID: 24172291.
  5. Melik Z, Zaletel P, Virtic T, Cankar K. L-arginine as dietary supplement for improving microvascular function. Clin Hemorheol Microcirc. 2017;65(3):205-217. doi: 10.3233/CH-16159. PMID: 27814280.
  6. Fayh AP, Krause M, Rodrigues-Krause J, Ribeiro JL, Ribeiro JP, Friedman R, Moreira JC, Reischak-Oliveira A. Effects of L-arginine supplementation on blood flow, oxidative stress status and exercise responses in young adults with uncomplicated type I diabetes. Eur J Nutr. 2013 Apr;52(3):975-83. doi: 10.1007/s00394-012-0404-7. Epub 2012 Jul 6. PMID: 22763798.
  7. Aguiar AF, Balvedi MC, Buzzachera CF, Altimari LR, Lozovoy MA, Bigliassi M, Januário RS, Pereira RM, Sanches VC, da Silva DK, Muraoka GA. L-Arginine supplementation does not enhance blood flow and muscle performance in healthy and physically active older women. Eur J Nutr. 2016 Sep;55(6):2053-62. doi: 10.1007/s00394-015-1019-6. Epub 2015 Aug 18. PMID: 26280946.
  8. Wilson AM, Harada R, Nair N, Balasubramanian N, Cooke JP. L-arginine supplementation in peripheral arterial disease: no benefit and possible harm. Circulation. 2007 Jul 10;116(2):188-95. doi: 10.1161/CIRCULATIONAHA.106.683656. Epub 2007 Jun 25. PMID: 17592080.
  9. Rhim HC, Kim MS, Park YJ, Choi WS, Park HK, Kim HG, Kim A, Paick SH. The Potential Role of Arginine Supplements on Erectile Dysfunction: A Systemic Review and Meta-Analysis. J Sex Med. 2019 Feb;16(2):223-234. doi: 10.1016/j.jsxm.2018.12.002. Erratum in: J Sex Med. 2020 Mar;17(3):560. PMID: 30770070.
  10. McRae MP. Therapeutic Benefits of l-Arginine: An Umbrella Review of Meta-analyses. J Chiropr Med. 2016 Sep;15(3):184-9. doi: 10.1016/j.jcm.2016.06.002. Epub 2016 Sep 10. PMID: 27660594; PMCID: PMC5021928.
  11. Brooks JR, Oketch-Rabah H, Low Dog T, Gorecki DK, Barrett ML, Cantilena L, Chung M, Costello RB, Dwyer J, Hardy ML, Jordan SA, Maughan RJ, Marles RJ, Osterberg RE, Rodda BE, Wolfe RR, Zuniga JM, Valerio LG Jr, Jones D, Deuster P, Giancaspro GI, Sarma ND. Safety and performance benefits of arginine supplements for military personnel: a systematic review. Nutr Rev. 2016 Nov;74(11):708-721. doi: 10.1093/nutrit/nuw040. PMID: 27753625.
  12. Sandbakk SB, Sandbakk Ø, Peacock O, James P, Welde B, Stokes K, Böhlke N, Tjønna AE. Effects of acute supplementation of L-arginine and nitrate on endurance and sprint performance in elite athletes. Nitric Oxide. 2015 Aug 1;48:10-5. doi: 10.1016/j.niox.2014.10.006. Epub 2014 Oct 24. PMID: 25445632.
  13. Meirelles CM, Matsuura C. Acute supplementation of L-arginine affects neither strength performance nor nitric oxide production. J Sports Med Phys Fitness. 2018 Mar;58(3):216-220. doi: 10.23736/S0022-4707.16.06680-9. Epub 2016 Sep 13. PMID: 27623757.
  14. Meirelles CM, Matsuura C, Silva RS Jr, Guimarães FF, Gomes PSC. Acute Effects of L-Arginine Supplementation on Oxygen Consumption Kinetics and Muscle Oxyhemoglobin and Deoxyhemoglobin during Treadmill Running in Male Adults. Int J Exerc Sci. 2019 Mar 1;12(2):444-455. PMID: 30899346; PMCID: PMC6413837.
  15. Pahlavani N, Entezari MH, Nasiri M, Miri A, Rezaie M, Bagheri-Bidakhavidi M, Sadeghi O. The effect of l-arginine supplementation on body composition and performance in male athletes: a double-blinded randomized clinical trial. Eur J Clin Nutr. 2017 Apr;71(4):544-548. doi: 10.1038/ejcn.2016.266. Epub 2017 Jan 25. Erratum in: Eur J Clin Nutr. 2017 Aug;71(8):1028. PMID: 28120856.
  16. Morris CR, Hamilton-Reeves J, Martindale RG, Sarav M, Ochoa Gautier JB. Acquired Amino Acid Deficiencies: A Focus on Arginine and Glutamine. Nutr Clin Pract. 2017 Apr;32(1_suppl):30S-47S. doi: 10.1177/0884533617691250. Epub 2017 Feb 1. PMID: 28388380.

More great content you may like

More great content you may like

Before you finish your last lap...

Don’t miss any of our great newsletters.